Automatic laser projection scanner with improved activation controlling mechanism

摘要

Disclosed is a fully automatic bar code symbol reading system having an hand-supportable laser bar code reading device which can be used in either an automatic hands-on mode of operation, or in an automatic hands-free mode of operation. The system includes a scanner support frame for supporting the hand-supportable device in a user-selected mounting position, and permits complete gripping of its handle portion prior to its use in the hands-on mode of operation. In general, the hand-supportable bar code reading device has long-range and short-range modes of object detection, bar code presence detection and bar code symbol reading. In the illustrative embodiment, the long-range mode is automatically selected when the hand-supportable bar code reading device is placed within the scanner support stand during the automatic hands-free mode of operation. Whenever the hand-supportable bar code reading device is picked up from the support stand and used in its hands-on mode of operation, the short-range mode is automatically selected to provide CCD-like scanner emulation. When used in either mode of operation, the automatic bar code reading device is capable of reading, in a consecutive manner, one or more bar code symbols on an object, while preventing multiple reading of the same bar code symbol due to dwelling of the laser scanning beam upon the bar code symbol. The automatic bar code symbol reading system of the present invention is disclosed in several different mounting arrangements at a point-of-sale station, illustrating novel methods of reading bar code symbols using the automatic hand-supportable laser scanning device of the present invention.